Approximately 200,000 patients per year in the U.S. undergo the surgical removal of lumbar disks. Candela Laser Corporation proposes to develop a laser based method for percutaneous decompression of herniated lumbar disks. A pulsed mid-infrared laser with a fiber optic delivery system will be used to ablate material and reduce the volume of the nucleus pulposus, achieving a clinically important reduction in intradisk pressure. Phase I results show that the laser approach was statistically equivalent to accepted automated percutaneous diskectomy methods in-vitro as measured by disk elastance (pressure/volume response). In-vivo studies in pigs showed that there were no untoward effects. Phase II efforts will yield an optimized system in terms of laser wavelength, energy and power. A delivery system will be refined and consist of a directable catheter which will have an option allowing visualization of the intradisk space. Preclinical studies in an in-vivo animal model will establish the rationale for extension to a limited clinical trial in the second year of the project. The laser method has the potential advantages of : a minimally invasive technique, a procedure performed on an outpatient basis, greater patient acceptance and a higher clinical success rete. Cost savings over conventional surgical techniques are anticipated.